Electric ignition-fuse.



K. SCILAPFLER, RBKTB GLUSSLQ ELECTRIC IGNITION FUSE APPLICATION FILED 0(JT.1,1912.

Patented Mar. 24, 1914 UNITED STATES PATENT ELECTRIC IGNITION-FUSE.

To all whom it may concern:

Be it known that I, KoNRAn SOHAFFLER,

relate GLossL, subject of the Emperor of Austria- Hungary, residing at Vienna, Austria-IIungary, have invented certain' new and useful Improvements in Electric Ignition-Fuses; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

Electric ignition fuses are used in series practically without exception, because a parallel connection'is on the one hand too complex and on the other hand the fuses cannot be easily tested after the train. has been laid. If now for any reason these fuses connected in series are not equally sen sitive to ignition the more sensitive are fired .While the less sensitive, owing to the interruption of the current caused by explosion of the sensitive fuses, are not fired and become so-called misfires.

The present invention has for its object to arrange the electrical ignition fuses so as to prevent with absolute security a misfire of the separate fuses, even in the case when the separate fuses that are connected in series are not equally sensitive to ignition. For this purpose the parts of the ignition lead which are to be connected with each other are arranged on that side of the insulating disk closing the charge chamber ,Which is farthest from the charge chamber so that these contact parts are actually brought into contact with each other, in consequence of the insulating disk being displaced by the explosion of the charge, and remain uninfiuenced by a vacuum which might be generated after the explosion of thecharge in the 'charge chamber, and which might produce the withdrawal or the ejection of the insulating disk.

In the accompanying drawings Figures 1, 3, 5, 7 and 8 show each a longitudinal section through a form of fuse made according to the present invention. Fig. 2 isa cross section on line AA of Fig. 1. Fig. at cross section on line B-B of Fig. 3, and Fig. 6 a cross section on line G--C of Fig. 5.

In Figs. 1 and 2 the i'nition electrodes 0 and at connected with t e firing leads I Specification of Letters Patent. Application filed October 1, 1912.

Patented Mar. 24, 1914. Serial No. 723,326.

and g consist of the Hat metal strips, one of wlnch c is provided with a U shaped contact piece 6 (Fig. 2) made of two folds of the metal strip a; this contact piece rests on a closing disk It held by a constriction of the casing a. Upon this contact piece 6 lies an insulating disk 2' of mica or the like and upon the latter there rests a tongue j fixed to the second electrode a or cut out from this; this tongue is as broad as the space between the limbs of the U shaped contact piece 0 or it is somewhat broader than this. The charge chamber .is closed below by an insulating disk it through which the electrodes 0, (i connected by the fuse wire 6 extend. The disk it rests on a pin Z, the lowerend of which abuts against the tongue 7'. A third insulating disk 71. holds pin Z firmly in the correct position, while a ring it? of insulating material surrounds the contact piece 6 and j and prevents the mica disk 1 from shifting. The charge chamber is closed above by a disk It and the whole fuse is rendered tight by cast masses mfm.

When the downward by the insulating disk hand causes the tongue j to shear through the mica disk (I and to enter between the arms of the U-shaped contact piece e where it is firmly held so that the electrodes are short circuited. Should the explosion produce a vacuum in the charge chamber the insulat ing diskh may be drawn backward, but the contact between the tongue 7' and the contact piece 6 is not affected, so that even should the insulating disk It be altogether removed the electrodes would remain short circuited.

In the construction shown in, Figs 1 and 2 the mica disk 71 might be dis ensed with, so that there is merely a layer of air between the tongue y and the contact piece 6. The pin Z will then be held in its upper position by the strength of the tongue In the construction shown in Figs 3 and 4 the electrodes 0 and d have a U-shaped cross section (Fig. 4). a tonguej in the other electrode 0 this slot to such an extent that its end is adapted to be engaged by an insulating disk arranged above the tongue j and to be depressed when the said disk is pushed downward by the explosion of the charge. The slot n is at its upper part broader than thetongue j andv tapers downward so that fuse is fired the pin Z'is forced and projects beyond the depressed end of the tongue is clamped in the slot when depressed by the insulating disk. lfhe space between the'electrodes 0, d is filled by a rod 0 of insulating material in which is a slot 39 to accommodate tongue 7'. lhe slot p is narrower than slot n and thus insures that the tongue j shall remain out of contact with the sides of the slot at. The upper edge of the slot p is lower than the upper edge of the slot at so that the end of tongue j cannot come-in contact with the, upper edge of slot n. Slut 10 therefore prevents unintentional short circuiting of the fuse wire. The upper ends of. electrodes 0 and (Z extend through an insulating disk 71?.

in the construction shown in- Figs. 5 and 6 the fuse casing a is shaped slightly conical and is made of paper. lhe electrodes 0, d consist of slightly conically shaped pieces of sheet metal kept separate from each other by the insulation at the bottom. part and the insulating disk It at the upper part, so that their edges cannot come in cont-act with each other. The electrode d carries atongue j above which is arranged an insulating disk it adapted to close the charge chamber is at its bottom. Electrode 0 has a slot at below which two folds g of the electrode 0 are bent inward. When the charge explodes the insulating disk It presses the tongue 9' between the folds g whereby the electrodes form a short circuit.

In the constructions shown in Figs. 3 and 6 the insulating disks it are preferably of soft material like fiber or compressed paper.

Figs. 7 and 8 show two further constructions-in which there are no separate contact pieces on the electrodes for the purpose .of short circuiting the latter at the moment of explosion, but the two electrodes are brou ht directly into contact with pach other. lfior this purpose the clcctrodes g and (Z are bent toward and away from each other beneath the insulating disk h which closeg the charge chamber in. In this manner there are formed two parts 0 of the electrode opposite to each other and so close together that when the insulating diskJz/ is driven downward and thus still further bends the electrodes the said parts are brought into contact with each other.

The insulating disk h is preferably provided in all constructions of the fuse with a circular flange (Fig. 8) extending into the charge chamber; the explosion gases press this flange against the inner surface of the casing and thus insure a satisfactory tightness of the charge chamber is.

In the constructions according to Figs. 1 to the parts of the firing leads of electrodes brought into contact with each other by the explosion remain unaffected by the vacuum occurring after the explosion in the charge chamber, which vacuum might draw back or even eject the insulating disk h; this result is achieved by arranging the parts which are to come in contact with each other beneath the insulating disk h or, more generally, on that side of the disk on which the charge is not situated. The short circuit brought about by the explosion is therefore not broken again by the vacuum.

The present invention may advantageously be applied also to electric fuses without a resistance Wire, that is to say the socalled gap incandescence fuses or spark fuses in which the charge is mixed with conducting particles.

1. An electric ignition fuse, comprising a casing, a charge chamber therein, electrical conductors for effecting ignition in said chambenand an insulating disk back of the charge chamber for maintaining the conductors insulated and operating upon ignicasing, a charge chamber therein, conductors: efi'ecting and an insulating having a peripheral flange and forming therear wall of said chamber, said disk maintaining said conductors insulated and operating to short circuit. the conductors upon ignition of the char e.

4. An electric ignition se, comprising a ignition in said chamber,

casing, a charge chamber therein, conductors effecting ignition in said chamber, and an insulating disk behind the chamber having a peripheral flange directed into thecharge chamber and 'in frictional engagement with said casing and forming the rear wall of said chamber, said disk maintaining said conductors insulated and operating to short circuit the conductors upon ignition of the charge.

5. An electric ignition fuse, comprising a casing, a charge chamber therein, electrical conductors for igniting the charge, and terminating in said chamber, an insulating disk for maintaining the conductors spaced apart, and means on the conductors actuated by said disk upon explosion of a charge in .said chamber to short-circuit the conductors.

6. An electric ignition fuse, comprising a casing, a charge chamber therein,electr1ca1 conductors for ignitiiig the. charge and terminating in said chamber, an insulating disk for maintaining theconductors spaced apart and means on the conductors comprising parts ofsaid electrodes capable of besk behind the chamber ing deformed by and actuated by said disk upon explosion of a charge in said chamber totshort circuit the conductors.

7. An electric ignition fuse comprising a casing, a charge chamber therein, electrlcal conductors for igniting the charge and terminating in said chamber, one of said conductors having a contact tongue and the other of said conductors having a contact cooperating with said tongue, and means for maintaining the electrodes normally separated and the contacts disengaged, said means operatin to close said contacts upon explosion of a c arge in said chamber.

8. An electric ignition fuse comprising a casing, a charge chamber therein, a flanged disk forming the back wall of said chamber and whose flange projects into the charge chamber, and conductors terminating in said chamber and normally maintained spaced apart, a contact tongue formed from one conductor and a contact on the other conductor cooperating with said tongue when said disk is rearwardly projected by the explosion of a charge in said chamber.

In testimony that I claim the foregoing as my invention I have signed my name in presence oitwo subscribing witnesses.

KONRAD SGHAFFLER, BEKTE GLGSSL. Witnesses:

AUGUST FUGGER, Josnr MERKLE. 

